Furnace.



No. 737,128. PATBNTED AUG. 25, .1903.

T. MURPHY.

FURNACE.

APPLIOATION IILED JUNE 25, 1901. RENEWED JUNE 25, 1903. N0 MODEL. 2 SHEETS-SHEET 1.

" PATBNT'ED AUG. 25, 1903.

T. MURPIiY.

FURNACE. AYPLIGATIQF FILED 111F325,

19'01. RENEWED JUNE 25, 1903.

no MODIBL.

40 into the ash-pit.

45 to give the desired heating effect.

UNITED STATES Fatented August 25, 1 908.

THOMAS MURPHY, OE DETROIT, MICHIGAN.

FURNACE.

SPECIFICATION forming part of Letters Patent 0. 737,128, dated August 25, 1903.

Application filedJune25, 1901. RenewedJune 25.1903. Serial 110.163.13 1. (No model.)

To all whom it may concern.-

- Be it known that I, THOMAS MURPHY,a citizen of the United States, residing at'Detroit, in the county'of Wayne and-State of Michigan, have invented certain new and'useful Improvements in Furnaces, of which the fol-; lowing is a specification, reference being had therein to the accompanying drawings.

The invention relates to that class of self IO feeding furnaces in which the fuel is gradually introduced into the furnace-chamber and is slowly fed over the grate from end thereof until consumed.

In'some of the figures of this application I have shown my invention as applied to a furnace of the type shown in my'prior patents, Nos. 316,641 and 316,642, of April 28, 1885, and in another figure'I have shown it as applied to a grate of the endless-chain type. The improvement is applicable toother types of furnaces, and it-isimmaterial which is used. 4

In such forward-feeding grates shown by my before-mentioned patentsit has been ous- 2 5 ternary to have the grate extend to the level of the feeding ledge or plate from which the fuel is fed from outside the furnace. In this arrangement the fuel is partially coked before being fed onto the grate and is then o pushed onto the upper end of the grate and be ignited by contact with thecdge of the burning fuel on the grate, and it is often pushed beneath the live fuel before it gets fairly ignited, so that a considerable quantity of fuel will fall between the grate-bars Furthermore, the effect of pushing the fresh fuel against the edge of the live fuel on the grate is to make a comparatively deadrspace for some distance-down the grate, thus requiring greater grate area My present invention is designed to overcome these objections, and this I accomplish by arranging the fuel-feeding deviceabove the level of the upper end of the grate. The fuel-ignit- 5o ing ledge is also arranged on a level with the fuel-feeding device and above the grate, and

between said fuel-igniting ledge and the grate is arranged a substantially vertical heat-reflecting wall or hot plate. With this arrangement the fuel when first introduced into the furnace-chamber is subjected to the heat thereof while supported upon the led ge,which will cause it to ignite, and when finally pushed off from said igniting-ledge it will fall upon top of the live fuelatthe. upper end of the grate, the fuel on the grate being always separated from that on the igniting-ledge. The

vertical wall or hot plate between the ignit ing-ledge and the grate acts as a reflector of heat, which prevents the fuel at the upper end of the gratefrom loss of heat through radiation out through the feed-aperture and also reflects the heat from the upper wall or. arch of the furnace upon the freshly-fed fuel on thegrate. The result is that the entire area of the grate-surface is effective in generating heat and that the fuel is maintained practically in incandescence over the entire area.

In the drawings, Figure 1 is a longitudinal section through the furnace to which my improvelnents are applied. Fig. 2 is a similar- ,view showing a modified form of furnace.

Fig. 3 is a sectional perspective view of a furnace of the type shown in Fig. 1. Fig. 4 is a sectional perspective view showing the fuelmagazine and arch. Fig. 5 is a cross-section showing the construction of the flat arch, and Fig. 6 is a sectional perspective view of the guide-bar for the fuel-pusher.

In Fig. 1 a furnace is shown comprisingan inclined grate A, at the lower end of which is arranged a rotary clinker-bar B and at the upper end fuel-feeding devices comprising a reciprocating fuel-pusher '0, supported upon the fuel-shelf D and below the fuel-hopper E. The shelf D is in line with an-aperture F through the furnace-wall, which is arranged above the level of the upper end of the grate. Below the aperture F is a substantially vertical wall or hot plate G, which is preferably the radiation of heat from the fuel at the upper end of the grate outward through the feed-aperture F. It also concentrates upon the fuel at the upper end of the grate the heat within the turn ace-chamber due directly to the combustion therein and to the reflection from the top wall or arch. Furthermore, as the wall G is subjected to the heat of the furnace it is itself highly heated or brought into a state of incandescence, so that it assists in the ignition of the fuel fed inward by the pusher O.

In Fig. 2 is shown a different type of furnace comprising an endless-chain grate A, adapted to move in the direction indicated by the arrow to feed the fuel gradually over from one side of the furnace to the other. With this type of furnace it is usual to feed the fresh fuel into the furnace-chamber directly upon and by means of the endless grate, and with such an arrangement the same difficulty referred to above is experienced in igniting the freshly-fed fuel. To overcome this objection;'I have arranged a wall G, preferably of refractory material, extending upward above the forward end of the grate, its upper surface a. forming a fuel supporting and igniting ledge and its upright surface I a heatrefiecting surface similar to the construction shown in Fig. 1.

In the operation of either of the furnaces shown the fuel is periodically fed inward by the pusher C from the magazine E onto the top ledge a or a, where it is allowed to remain fora short interval exposed to the heat of the furnace, as well as that of the heated wall G or G, so that it is ignited before being fed off over the ledge or shelf. When thus pushed off, it falls upon the top of the burning fuel on the grate, and as it has been already ignited and is protected by the reflecting-wall b or b from loss of heat itwill quickly be brought into a state in incandescence and will immediately generate a considerable amount of heat.

In Figs. 3, 4c, and 5 is shown a furnace simi lar in type to that shown in Fig. 1, but provided with certain additional improved features of construction. In Fig. 5 is shown a flat arch H, which forms the top of the fuelpocket F and which joins with the rounded arch I, covering the furnacechamber. This construction permits of forming the pocket F of equal height from one end to the other, so that a uniform quantity of fuel may be fed therethrough the entire length of the grate. To provide for the expansion which results from the process of heating the fuel, the pocket F may be formed flaring toward its inner end by inclining the end face of the arch H, as shown. In order to prevent any Fig. 3.

a poker to dislodge any fuel at the upper end of the grates. The guide-bar L, which is arranged above the fuel-pusher O and to which the fuel-hopper E is seen rod, is also preferably formed with apertures, such as M, through which a poker may be introduced into thev fuel-pocket.

The fuel-hopper E is preferably constructed as shown in Figs. 3 and 4, in which a is an inclined front plate hinged at its lower end to the bar L. At opposite ends of this plate are secured the end plates (1, which extend inward to the rear plate 6 and are detachably secured to the latter by hooks f or other suitable fastening means. The lid 9 of the hopper is hinged to the front plate. The arrangement permits of turning down the hopper out of the way of the opening into the furnace, so that if the fuel in the pocket should become clogged a poker may be introduced to dislodge it.

What I claim as my invention is- 1. In a furnace, the combination with a grate adapted to feed the fuel thereon inward from one edge thereof, of a refractory wall extending upward adjacent to said edge of the grate to above the height of the fuel there on, the top of said wall forming a fuel supporting and igniting ledge extending substantially the entire width of the grate and upon which the fuel may be fed from outside the furnace andthe innerface ofsaid Wall forming a heat-reflecting surface protecting the fuel at the edge of the grate from loss of heat through the feed -opening or from contact with unignited fuel.

2. In a furnace, the combination with a grate adapted to automatically feed the fuel thereon inward from front to rear, of a front wall having a fuel-aperture therein forming a ledge extending the entire width of the grate and above the level of the fuel thereon, said ledge forming a fuel supporting and igniting shelf, and means for feeding the fuel inward through said aperture onto said ledge and for pushing it off of said ledge when properly ignited and dropping it upon top of the fuel on top of the grate.

3. In a furnace, the combination of a grate, means for feeding the fuel inward from one edge thereof, a refractory wall at said edge, said Wall having a fuel supporting and igniting surface over which the fuel is fed from the outside terminating at the feed edge of the grate above the level of the fuel thereon, and substantially the entire width of the grate and said wall also having a substantially vertical heat-reflecting surface extending to at or near the feed edge of the grate for the purpose described.

4. In a furnace, the combination with a grate having means for feeding the fuel thereon from one edge thereof, of an igniting-ledge having a heat-reflector extending downward from its inward edge, said ledge being arranged above the normal level of the fuel on said grate at the feed end thereof, and ex.-

tending substantiallythe full width of the grate and means for first feeding the fuel onto said igniting-ledge and then dropping the same from off said ledge upon top of the fuel on said grate.

5. In a furnace, the combination with the grate inclined downward from front to rear, of a front wall and having a fuel-aperture therein forming a ledge extending the entirewidth of the grate and above the level of the upper end thereof, and means for feeding fuel through said aperture fromsaid ledge and on top of the live fuel at the upper end inclined grate of a wall extending up above. the upper end of said grate forming a fuel-- shelf from which the fuel is dropped upon the upper end of said grate, said Wall being provided with a series of poking-apertures therethrough just above the grate.

8. Ina furnace, the combination of a wall having a fuel-feed aperturetherein, a reciprocating pusher for feeding the fuel through said apertures and a fuel-hopper outside said wall, and a guide-bar for the pusher to which the lower end of said hopper is secured, said guide-bar having poking-apertures formed therethrough.

9. In a furnace, the combination of a wall having a fuel-feed'aperture therein, a reciprocating pusher for feeding the fuel through saidaperture, a guide-bar for said pushers arranged abovethe same and outside said 1 wall, and a hopper hinged to said guide-bar and adapted to fold down for the purpose described.

In testimony whereof I affix my signature in presence of two witnesses.

THOMAS MURPHY. Witnesses: I

M. B. ODO HERTY, H. G. SMITH. 

